While many of us living in Northeast Mesa enjoy the hiking terrain practically in our backyards, and we admire the saguaros and cacti so unique to Arizona’s landscape, many also may have noticed other plants, which don’t really fit into what one might imagine is desertscape.
Many of these plants are not quite as innocuous as they might first appear. Non-native invasive plants, introduced both inadvertently and intentionally over the years, from as far away as Russia and Africa, have become a real threat to the Sonoran Desert, including Tonto National Forest. The U.S. Forest Service, in Mesa, has identified six particularly noxious plants. The culprits are Fountain Grass, Buffelgrass, Salt Cedar, Saharan Mustard, Malta Starthistle and Tree of Heaven.
Recently, volunteers met at the Mesa Ranger District office to hear Ranger Patti Fenner and Volunteer Ranger Don Pike discuss the characteristics of these plants and ways in which to slow down their exponential growth and proliferation in our area.
“The major problem with these plants is their fibrous roots mine so deep into the soil that they out compete native plants for critical water supplies,” Patti explained. “Non natives drop leaves so high in salts that they poison the surface soil such that native plants cannot grow or reproduce.”
One of the scariest realities is these plants provide fire ladders to native trees and saguaros, burning at temperatures as high as 1400 degrees Fahrenheit. This holds fire around the base of a plant, from which there is no escape.
“Malta Starthistle is particularly dangerous for horses,” Patti added. “When ingested, lesions form on the brain, leading to throat paralysis and ultimate death from starvation. Salt Cedar crowds out native riparian trees, increases soil salinity and changes the channel characteristics of streams,” she further stated. “If the sap from a Tree of Heaven enters an open wound, it can cause heart problems.”
These are just a few examples of why we need to eradicate invasive species. Economically, the issue affects us all. The state pays millions in removal of these weeds from highways, and bigger long-term concerns include the effect on the water table.
What is being done? Don Pike demonstrated how he has mapped the locations of invasives using geo-coding and a Web site, iMapInvasives.org. This is an area where individuals can help, by volunteering to send data to the U.S. Forest Service as to where invasive plants have been spotted.
How are these plants being dealt with on the ground? The Forest Service has used herbicides, and has mechanically dug out and burned invasive plants. Individuals can remove plants from their property, and encourage local landscapers not to sell these as nursery products. “With 3 million acres of land lost to invasive weeds every year, it’s going to have to be an ongoing effort,” said Don, “because the plants are spreading in a alarming way.”
Further information can be obtained from the Mesa Ranger District, located at 5140 E. Ingram St. Visit the Web site at www.mrdvolunteers.org, or call (480) 610-3300.